Abstract

Non-coding RNAs (ncRNA), a significant part of the increasingly popular dark matter of the human genome, have gained substantial attention due to their involvement in animal development and human disorders such as cardiovascular diseases and cancer. Although many different types of regulatory ncRNAs have been discovered over the last 25 years, microRNAs (miRNAs) are unique within these as they are the only class of ncRNAs with individual genes sequentially conserved across the animal kingdom. Because of the conserved roles miRNAs play in establishing robustness of gene regulatory networks across Metazoa, it is important that homologous miRNAs in different species are correctly identified, annotated, and named using consistent criteria against the backdrop of numerous other types of coding and non-coding RNA fragments.